Field of the Invention
The present invention relates to an aqueous solution containing bis(Nε-lauroyl lysine)dicarboxylic acid diamide and/or a salt thereof, and a production method thereof.
Discussion of the Background
It has been reported that bis(Nε-lauroyl lysine)dicarboxylic acid diamide and a salt thereof are useful as gelling agents for water and organic solvents (non-patent document 1). In non-patent document 1, Nε-lauroyl-L-lysine and dicarboxylic acid dichloride are reacted in a mixed solvent of water and diethyl ether, the reaction solution is acidified with hydrochloric acid, and the resultant product is precipitated and filtrated, whereby bis(Nε-lauroyl lysine)dicarboxylic acid diamide is produced. Furthermore, a salt thereof is produced by adding a base (non-patent document 1, page 1440, Scheme 1 and page 1442, General procedure).